Most of the recent studies on broadcast based data dissemination approach have an implicit assumption that the server is able to broadcast consistent data to the mobile clients. However, this assumption may not be valid unless there is a special algorithm to handle broadcasting data in a consistent and timely manner. In this work, we address a number of issues related to this problem. An efficient...
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A challenging area of ubiquitous wireless computing is the provision of system software for mobile programmers. We propose a software architecture for a compiler in a mobile environment. The solution does not require lower level details of the wireless communication, protocols and hardware platform of mobile computers. The design takes into consideration the resource constraints of the mobile host...
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With the advent of mobile computers, new challenges arise for software designers. The paper focuses on disconnected operation: making mobile computers work well on shared data whether the network is available or not. Initially the shared data is cached on the mobile computer. Modifications and additions to this cached data will be reconciled with the shared data when the mobile computer is reconne...
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The rapid growth of Internet access from mobile users has emphasised the importance of location specific information on the Web. A unique Web service called Mobile Info Search (MIS) from NTT Laboratories gathers information and provides location aware search facilities. We performed association rule mining and sequence pattern mining against an access log which was accumulated at the MIS site in o...
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Bluetooth is a relatively new wireless technology that holds much promise as an inexpensive, power conserving, pervasive global standard for short-range communication with support for voice, data, ad-hoc networking and LAN access. A scalable LAN access solution based on Bluetooth, called blu21, has been developed by Siemens to support information access via mobile devices in enterprise and public ...
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In this paper, we reexamine the issue of selective tuning using the flexible indexing scheme by T. Imielinski et al. (1994) in the context of unreliable wireless channels. We propose a mechanism that can be applied to uniform and nonuniform broadcast to enable a client using the scheme to recover from errors.
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In this paper, we propose a framework of Internet marketplaces on the basis of mobile agent. It not only simulates real commercial activities by consumers, agents and merchants, but also provides an environment for parallel processing. The latter is particularly important as more shops (sites) can be searched in real time to provide consumers with better choices. The conducted experiments show tha...
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With the growing popularity of mobile computing devices and wireless communications, managing dynamically changing information about moving objects is becoming feasible. In this paper we implement a system that manages such information and propose an efficient range query algorithm with a filtering step which efficiently determines if a polyline corresponding to the trajectory of a moving object i...
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Most existing distributed file systems (DFS) implement a single consistency model to maintain one-copy equivalence. The functionality of that consistency model is based on a balance between environmental constraints and the targeted level of consistency. Such systems efficiently maintain consistency while the environmental capabilities remain constant, for example, presuming uninterrupted connecti...
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Recent advances in computer and wireless communication technologies have led to an increasing interest in ad hoc networks which are temporarily constructed by only mobile hosts. In ad hoc networks, since mobile hosts move freely, disconnections occur frequently, and this causes frequent network division. Consequently, data accessibility in ad hoc networks is lower than that in the conventional fix...
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UCS-Router (E. Bertino et al.) is a policy engine developed for message dispatching in a Universal Communication System. A user of the system has a unique identifier, named Universal Communication Identifier (UCI), independent from the actual communication devices the user owns. It is a task of the UCS-Router to properly route messages or phone calls arriving at the UCI to the proper user devices....
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Tracking the location of people, computers, vehicles, and other mobile objects and performing computation on such location data are quickly gaining interest. The idea of location-based services has captured the imagination of application developers, wireless service providers, and content providers alike. However, the location of people, the most interesting mobile object, is tricky to determine b...
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The mobile agent approach is suitable for deploying large-scale parallel processing over distributed hosts. However, if the number of mobile agents is very large and the dispatch is processed in a serial way, it can become a bottleneck that impacts the efficiency as a whole. In this paper, we first briefly present a mobile agent based framework for Internet marketplaces enabling parallel processin...
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Mobile IP is an Internet protocol designed to support host mobility. It provides the host the ability to stay connected to the Internet regardless of its location. This paper presents a modified Mobile IP protocol, (Dynamic Mobile (IP-DM-IP)). DM-IP eliminates triangular routing, which exists in current Mobile IP and it can be easily implemented in the existing wireless infrastructure. In DM-IP th...
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Many approaches have been proposed to schedule data items for broadcasting in a mobile environment. However, the issues of accessing multiple data items on the broadcast channel are less discussed. In this paper, an efficient strategy for accessing multiple data items in mobile environments is proposed. Two issues are investigated in this paper, that is, deciding the content of the broadcast chann...
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The main objective of the EU-promoted project MOVE (Mobile Middleware with Voice-Enabled Services, http://move.rwth-aachen.de) was the integration of voice (real-time data) and multimedia services (non-real-time data) for mobile GSM- and UMTS-based communication, transmitted via the Internet Protocol. An architecture was developed which was enhanced with an API for service providers. It permits th...
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The mobile environment is inherently asymmetric. To utilize the downstream bandwidth effectively, hot data items should be disseminated over the broadcast channel to the mobile clients. To equip clients with the ability to identify the nature of the broadcast and to determine the answerability of their queries, semantic descriptions are associated with information units in the broadcast, organized...
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In this paper we devise data allocation algorithms that can utilize the knowledge of user moving patterns for proper allocation of shared data in a mobile computing system. By employing the data allocation algorithms devised, the occurrences of costly remote accesses can be minimized and the performance of a mobile computing system is thus improved The data allocation algorithms for shared data, w...
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Rapid, sustained advances in key computing hardware technologies combine to enable a new class of computing services that aim to meet the needs of mobile users. These ubiquitous and intelligent services adapt to each user's particular preferences and current circumstances, i.e., they are personalized. The services exploit data available front multiple sources, including data on past interactions w...
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BlueLocator, a framework enabling enterprise location-based services as well as an enterprise user locating and tracking system, is introduced in this paper. Privacy control in LBS is discussed and a report-to-chain based access control list assignment policy is shown as an example of how a privacy related rule can be used for applications.
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We present a framework for supporting multi-device stream orchestration for mobile users. As computing power becomes cheaper and larger numbers of devices become networked, we believe that users will have access to multiple devices in their neighborhood. Such a multi-device environment presents a significantly powerful environment for mobile users compared to thin wireless clients. Our architectur...
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There will soon be a huge number of data sources accessible to applications across the Internet. These include Web services, personal devices such as cellular phones and cars, and sensors measuring physical phenomena. New classes of data-composition applications can exploit this data. However, the data is diverse, voluminous, and often rapidly changing. The sources of data can be mobile, distribut...
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In a wireless environment, the bandwidth of the channels and the energy of the portable devices are limited. Data broadcast has become an excellent method for efficient data dissemination. In this paper the problem for generating a broadcast program of a set of data items with the associated access frequencies on multiple channels is explored. In our approach, we consider allocating index informat...
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